Popular Science is the fifth oldest continuously-published monthly magazine—a long way of saying that the magazine has done a fine job of maintaining a niche in a crazily fast-paced industry.

Most “optical illusions” are not really optical. They have less to do with the way the eyes work than with the way the brain processes the information sent to it from the eyes. For this reason, many scientists prefer to call them visual illusions.

This map shows the oldest light in our universe, as detected by the Planck mission. Click on the map for a larger image.
By now the Big Bang theory is widely accepted scientifically. The idea is that the universe began to expand rapidly about 14 billion years ago from a dense, hot state and continues to expand to this day.

Here’s an extraordinary recording of Albert Einstein from the fall of 1941, reading a full-length essay in English:

The essay is called “The Common Language of Science.” It was recorded in September of 1941 as a radio address to the British Association for the Advancement of Science.

We’ve written a fair amount on the various facets of Thomas Edison’s career, and somewhat less on his less-famous former employee-become-rival Nikola Tesla (who seems to polarize people in ways Edison doesn’t). Both inventors provoke all kinds of serious speculation, commentary, and debate.

Before you do anything else, click on the image above and then move little slider (along the bottom of the image) from left to right. Now watch the universe fly by, going from macro to micro.

Name the three figures, living or dead, with whom you would most like to sit down to dinner. Though perhaps a little tired, the challenge still reveals something worth knowing about the respondent’s personality.

We all need guides for the overwhelming world of the Internet. Digital curators are essential to sifting through the vast and expanding supply of online content because they find the good stuff that’s worth checking out.

Once upon a time, the larvae of the Caddis Fly were considered pretty unassuming creatures, freshwater dwellers whose appeal was limited to trout and trout fishermen. That is until French artist Hubert Duprat came along with an aesthetic offer they couldn’t refuse.

Like an invisible sculptor, the wind slowly shapes the natural world, bending Monterey Pines along California’s coast to reach horizontally towards the land, and whipping dry beach dunes into peaks.